Research on the calibration method for gear shifting of automatic transmission

The development process of electronic automatic transmission control system includes hardware development, software development and calibration. Calibration is the key step to implement control strategy and optimize control quality. An open loop control strategy for 1-2 shifting process was determined for the Allison 2000 transmission. The control pressure characteristics of on-coming clutch and off-going clutch were considered by the control strategy. By analyzing the control parameters, the calibration method and calibration procedure for gear shifting were proposed. The optimization object of the calibration method is to reduce the shift jerk with an acceptable shift time. The calibration method and calibration procedure were verified by the 1-2 upshift experimental study. The experimental study was carried out on the test bench under different load conditions. The experimental results show that superior shift quality is achieved following the calibration method and calibration procedure.